Safety and efficacy comparison of Tenecteplase and Alteplase for clinically suspected large vessel occlusion strokes without thrombectomy.

INTRODUCTION: Tenecteplase is a thrombolytic with higher fibrin affinity, and is potentially better in clot lysis. A higher spontaneous recanalization rate for large vessel occlusions strokes (LVO) had been shown in comparison studies with Alteplase. Results of the LVO studies reflect the composite effect of the thrombolytic and thrombectomy, as patients would be treated by thrombectomy had they not been recanalized by intravenous thrombolysis alone. Thrombectomy is not readily available in many parts of the world. Our study aimed to compare the outcomes of suspected LVO patients treated with Tenecteplase versus Alteplase only, without the confounding effect of thrombectomy. METHODS: This is a retrospective review. Data of patients given Tenecteplase from May 2020 to August 2023, and those given Alteplase 0.9 mg/kg from January 2019 to August 2023 were retrieved. (Due to fluctuation in supply of Tenecteplase during the COVID pandemic, some large vessel occlusion patients were given Alteplase.) Patients with anterior circulation, clinically suspected large vessel occlusion strokes (defined as National Institutes Health Stroke Scale (NIHSS) score >= 6, plus cortical signs or hyperdense vessel sign), with thrombolysis given within 4.5 hours of stroke onset were analyzed. Patients with thrombectomy done were excluded. Safety and efficacy outcomes were compared. RESULTS: There were 245 Tenecteplase treated patients treated between 1st May 2020 and 31st August 2023, and 732 patients were treated with Alteplase between 1st January 2019 to 31st August 2023. Out of these, 148 Tenecteplase patients and 138 Alteplase 0.9 mg/kg patients fulfilled the study criteria. The symptomatic intracerebral haemorrhage rate was non-significantly lower in the Tenecteplase group (2.1% versus 5.8%, p=0.13). There were no significant differences in the rate of >=8 points NIHSS improvement (23.6% versus 23.7%, p=1) or the >= 4 points improvement (40.5% versus 40.7%, p=1) at 24 hours. At 3 months, 21.6% of Tenecteplase patients had good functional outcome (modified Rankin scale (mRS) 0-2), compared to 26.3% in the Alteplase group (p=0.40). CONCLUSION: In this pragmatic study of clinically suspected anterior circulation LVO patients without thrombectomy, outcome solely reflects the effects of Tenecteplase. Tenecteplase showed comparable safety and efficacy to Alteplase. But the result should be interpreted with caution in view of its small sample size and non-randomized study design.

Improvement of Echinacea purpurea and Ganoderma lucidum Extracts with Cell Model on Influenza A/B Infection.

Since 2019, COVID-19 has been raging around the world. Respiratory viral infectious diseases such as influenza and respiratory syncytial virus (RSV) infection are also prevalent, with influenza having the ability to cause seasonal pandemics. While vaccines and antiviral drugs are available to prevent and treat disease, herbal extracts would be another option. This study investigated the inhibitory effects of extracts of Echinacea purpurea (EP) and Ganoderma lucidum (G. lucidum) and the advanced G. lucidum drink (AG) on influenza A/B viruses. To determine whether EP and G. lucidum extracts enhance cell immunity and thus prevent virus infection or act to directly suppress viruses, cell survival and hemagglutination (HA) assays were used in this study. Cells were treated with samples at different concentrations (each sample concentration was tested from the highest non-cytotoxic concentration) and incubated with influenza A/B for 24 h, with the results showing that both G. lucidum and EP extracts and mixtures exhibited the ability to enhance cell survival against viruses. In the HA assay, AG and EP extract showed good inhibitory effect on influenza A/B viruses. All of the samples demonstrated an improvement of the mitochondrial membrane potential and improved resistance to influenza A/B virus infection. EP and G. lucidum extracts at noncytotoxic concentrations increased cell viability, but only AG and EP extract directly decreased influenza virus titers. In conclusion, results indicate the ability of EP and G. lucidum extract to prevent viruses from entering cells by improving cell viability and mitochondrial dysfunction and EP extract showed direct inhibition on viruses and prevented viral infection at post-infection strategy.

A synthetic moving-envelope metasurface antenna for independent control of arbitrary harmonic orders.

Flexible frequency controls are crucial in many photonic and electronic applications, ranging from communications systems, spectroscopy, and metrology to quantum information processing. However, the state-of-the-art solutions based on nonlinear bulk media, electro-optic effect, and nonlinear metasurfaces incur very limited spectral controllability, and merely a couple of harmonic orders can be independently manipulated. Here, we theoretically propose and experimentally demonstrate synthetic moving-envelope metasurface antennas capable of simultaneously generating arbitrary harmonic orders and independently manipulating their wave properties in a software-defined manner. As proof-of-principle examples, we demonstrate unidirectional frequency transition, frequency comb generation, arbitrary harmonic orders independent control, and their applications in frequency-division multiplexing communications. All these complicated functionalities are achieved by the 1-bit spatiotemporally ON-OFF switching of meta-atoms of the waveguide-integrated metasurface antenna. Our proposed synthetic metasurface antenna solution greatly expands the frontiers of wave engineering and information manipulation, showing promising potential in wireless communications, spectroscopy, metrology, and quantum science.

Coping Mechanisms and Their Associations with Depression and Anxiety Among Healthcare Workers in the Aftermath of COVID-19 Pandemic.

OBJECTIVE: This study investigated the associations between anxiety, depression, and coping in healthcare workers (HCWs) during COVID-19. METHODS: A survey used the Generalized Anxiety Disorder-2 to assess anxiety, the Patient Health Questionnaire-2 to assess depression, and the Brief COPE scale to evaluate coping mechanisms. RESULTS: Of the 1,172 participants who provided data, 24.7% screened positive for anxiety and 15.7% for depression. Logistic regression indicated that avoidance coping (OR = 3.92 (95% CI: 2.91-5.29), p < .001) and substance use coping (OR = 1.39 (95% CI: 1.00-1.90), p = .049) were associated with higher odds of depression. Avoidance coping (OR = 2.81 (95% CI: 2.15-3.67), p < .001), and social support coping (OR = 1.59 (95% CI: 1.22-2.08), p = .001) were associated with higher odds of anxiety. CONCLUSIONS: Interventions are needed to improve HCWs' coping and wellbeing.

Terahertz spoof plasmonic neural network for diffractive information recognition and processing.

All-optical diffractive neural networks, as analog artificial intelligence accelerators, leverage parallelism and analog computation for complex data processing. However, their low space transmission efficiency or large spatial dimensions hinder miniaturization and broader application. Here, we propose a terahertz spoof plasmonic neural network on a planar diffractive platform for direct multi-target recognition. Our approach employs a spoof surface plasmon polariton coupler array to construct a diffractive network layer, resulting in a compact, efficient, and easily integrable architecture. We designed three schemes: basis vector classification, multi-user recognition, and MNIST handwritten digit classification. Experimental results reveal that the terahertz spoof plasmonic neural network successfully classifies basis vectors, recognizes multi-user orientation information, and directly processes handwritten digits using a designed input framework comprising a metal grating array, transmitters, and receivers. This work broadens the application of terahertz plasmonic metamaterials, paving the way for terahertz on-chip integration, intelligent communication, and advanced computing systems.

The Suprainguinal Fascia Iliaca Block Prolonging Spinal Anesthesia Duration.

Spinal anesthesia is commonly used for lower limb procedures, its duration may be limited with potential complications due to high doses of local anesthetic. This study describes the technique and experience of using suprainguinal fascia iliaca block (SIFI) as an adjunct to spinal anesthesia in an elderly patient undergoing lower extremity surgery. The case presented here involves an 81-year-old female undergoing hip surgery, where a SIFI block was performed prior to the administration of spinal anesthesia. Despite the unexpectedly prolonged surgical duration of approximately 5 hours, the patient remained comfortable, and the surgery was completed without complications. Subarachnoid block for provision of surgical anesthesia generally lasts between 2 and 3 hours with dose-dependent local anesthetic-related adverse effects. This may hinder the utility of spinal anesthesia in complex cases where extended surgical duration may be expected. The continuous spinal anesthesia and combined spinal-epidural (CSE) are useful techniques to provide consistent peri-operative anesthesia with precise titration of anesthesia levels. However, this presents with a risk of accidental dural puncture with CSE, post-dural puncture headache, and inadvertent drug errors with a spinal or epidural catheter. The judicious use of other adjuvants alongside local anesthetics offers advantages in extending the duration of anesthesia by a modest increment. The integration of spinal anesthesia with SIFI is a promising strategy to extend block duration, reduce peri-operative opioid requirements, and enhance patient outcomes. Overall, SIFI is a safe anesthetic technique for the peri-operative management of hip fracture patients and may present synergistic effects when combined with spinal anesthesia and may prolong the duration of regional anesthesia during unexpectedly prolonged surgery.

No increased risk of tuberculosis-related immune reconstitution inflammatory syndrome with integrase inhibitor-based antiretroviral therapy in people with HIV with profound immunosuppression.

INTRODUCTION: The issue of whether integrase inhibitors (INSTIs) may confer a higher risk of paradoxical tuberculosis-related immune reconstitution inflammatory syndrome (TB-IRIS) compared with other classes of antiretroviral in people with HIV with a profound level of immunosuppression remains insufficiently explored. We aimed to assess whether such a higher risk exists by examining a cohort of patients with TB-HIV initiating antiretroviral therapy (ART) in Hong Kong. METHODS: This was a retrospective review of 133 patients registered in the TB-HIV Registry of the Department of Health during the period 2014-2021. RESULTS: Sixteen of 70 patients (22.9%; 95% confidence interval [CI] 13.0-32.7) and 14 of 63 patients (22.2%; 95% CI 12.0-32.5) from the INSTI and non-INSTI groups experienced TB-IRIS (p = 0.920). The median intervals between ART initiation and IRIS among patients from the two groups were similar (3 weeks [interquartile range IQR 2.0-7.8] vs. 4 weeks [IQR 2.0-5.1], p = 0.620). The proportion of patients requiring steroid therapy were similar, as were the hospitalization rates. There was no IRIS-related death in either group. The risk of TB-IRIS with INSTI versus non-INSTI was also similar in a stratified analysis in a subgroup of patients with a baseline CD4 count of <50 µL (10/33 [30.3%; 95% CI 14.6-46.0] vs. 10/22 [45.5%; 95% CI 24.7-66.3], p = 0.252) and another subgroup of patients with ART initiated within 4 weeks of anti-TB treatment (10/26 [38.5%; 95% CI 19.8-57.2] vs. 10/23 [43.5%; 95% CI 23.2-63.7], p = 0.721). CONCLUSION: Our cohort study did not offer support for an increased risk of TB-IRIS with INSTIs compared with non-INSTIs, even in severely immunocompromised people with HIV.

A 2-year prospective evaluation of the Prostate Health Index in guiding biopsy decisions in a large cohort.

OBJECTIVES: To prospectively evaluate how the Prostate Health Index (PHI) impacts on clinical decision in a real-life setting for men with a prostate-specific antigen (PSA) level between 4 and 10 ng/mL and normal digital rectal examination. PATIENTS AND METHODS: Since 2016, the PHI has been available at no cost to eligible men in all Hong Kong public hospitals. All eligible patients who received PHI testing in all public Urology units (n = 16) in Hong Kong between May 2016 and August 2017 were prospectively included and followed up. All included men had a PHI test, with its result and implications explained; the subsequent follow-up plan was then decided via shared decision-making with urologists. Patients were followed up for 2 years, with outcomes including prostate biopsy rates and biopsy findings analysed in relation to the initial PHI measurements. RESULTS: A total of 2828 patients were followed up for 2 years. The majority (82%) had PHI results in the lower risk range (score <35). Knowing the PHI findings, 83% of the patients with elevated PSA decided not to undergo biopsy. In all, 11% and 45% opted for biopsy in the PHI score <35 and ≥35 groups, respectively. The initial detection rate of International Society of Urological Pathology (ISUP) Grade Group (GG) ≥2 cancer was higher in the PHI score ≥35 group (23%) than in the PHI score <35 group (7.9%). Amongst patients with no initial positive biopsy findings, the subsequent positive biopsy rate for ISUP GG ≥2 cancer was higher in the PHI score ≥35 group (34%) than the PHI score <35 group (13%) with a median follow-up of 2.4 years. CONCLUSION: In a real-life setting, with the PHI incorporated into the routine clinical pathway, 83% of the patients with elevated PSA level decided not to undergo prostate biopsy. The PHI pathway also improved the high-grade prostate cancer detection rate when compared to PSA-driven strategies. Higher baseline PHI predicted subsequent biopsy outcome at 2 years. The PHI can serve as a tool to individualise biopsy decisions and frequency of follow-up visits.

The effect of hydrostatic pressure on lipid membrane lateral structure.

High pressure is both an environmental challenge to which deep sea biology has to adapt, and a highly sensitive thermodynamic tool that can be used to trigger structural changes in biological molecules and assemblies. Lipid membranes are amongst the most pressure sensitive biological assemblies and pressure can have a large influence on their structure and properties. In this chapter, we will explore the use of high pressure small angle X-ray diffraction and high pressure microscopy to measure and quantify changes in the lateral structure of lipid membranes under both equilibrium high pressure conditions and in response to pressure jumps.

Comparing the acute toxicities of co-exposure to cocaine and ethanol versus cocaine alone.

INTRODUCTION: Cocaine is commonly consumed with ethanol, which leads to the formation of cocaethylene through transesterification. Cocaethylene is an active metabolite of cocaine with a longer duration of action. Literature on the combined toxicity of cocaine, ethanol, and cocaethylene is conflicting. We aimed to compare the acute toxicities of co-exposure to cocaine and ethanol versus cocaine alone in Hong Kong. METHODS: This was a retrospective study on acute cocaine toxicities reported to the Hong Kong Poison Control Center from 1 January 2010 to 22 January 2023. Cocaine exposure was confirmed by urine immunoassays/laboratory tests and ethanol co-ingestion was confirmed by blood ethanol concentrations. A serious outcome was defined as a National Poison Data System outcome moderate or above. Univariate analyses and multivariable logistic regression were performed to compare the associations of clinical outcomes with and without ethanol, followed by subgroup analyses of cases with complete data. RESULTS: We analyzed 109 patients (median age 29 years, 71% men, 68% Chinese), of whom 20 had confirmed ethanol co-ingestion (mean blood ethanol concentration 1350 mg/L). Multivariable analysis showed that co-exposure to cocaine and ethanol was associated with a lower risk of serious outcomes (adjusted odds ratio 0.09, 95% confidence interval 0.01-0.77; p = 0.03) after adjusting for age, sex, ethnicity, route of cocaine administration, and physical health status. Subgroup analyses showed similar findings. CONCLUSIONS: In contrast to previous studies, we did not identify a higher risk of serious outcomes after co-exposure to cocaine and ethanol compared to cocaine alone in a predominantly Chinese cohort.

Suicidal ideation among non-physician hospital system staff: Prevalence and workplace correlates.

BACKGROUND: Research suggests that healthcare workers are at greater risk for suicide than other occupations, but most published studies focus on physicians. This study examines the prevalence of suicidal ideation (SI) and associated occupational factors among a broad group of non-physician healthcare staff. METHODS: An anonymous online survey was sent to a random sample of 30 % of non-physician healthcare staff at a large urban healthcare system between September and November 2022. Weighted multivariable binary logistic regressions were conducted to determine the workplace and mental health factors associated with SI. RESULTS: The 1084 respondents included nurses, administrative staff, research staff, medical assistants, nurse practitioners, physician assistants, and other roles. Of the sample, 8.8 % endorsed having SI over the prior two weeks. Results of the regression indicated that, after adjusting for demographic factors, greater odds of SI were associated with physical violence experienced from a patient or visitor (odds ratio [OR] = 2.15, 95 % confidence interval [CI] = 1.06-4.37), lower perceived leadership support (OR = 0.95, 95 % CI = 0.92-0.98), and positive screening for depression (OR = 4.66, 95 % CI = 2.45-8.86). Exploratory analysis suggests that depression may be a mediating factor between workplace stressors and SI. LIMITATIONS: Limitations include the response rate, the use of a single item to assess SI, and the cross-sectional design. CONCLUSION: Findings suggest that workplace violence and leadership support are important occupational factors associated with SI among healthcare workers. Reducing and mitigating workplace violence, enhancing leadership support, and improving access to mental health care should be considered targets for interventions to decrease suicide risk in this population.

Research progress on sexual functioning and associated factors in childhood cancer survivors: a scoping review.

Background: Childhood Cancer Survivors (CCSs) are more likely to report sexual dysfunction than people without cancer history. Sexual functioning encompasses more than just sexual dysfunction. The scarcity of information regarding the status and influencing factors of sexual functioning in CCSs, hampers to devise suitable screening or interventions. This review aims to summarize research progress on sexual functioning and associated factors among CCSs. Methods: This review protocol is registered in PROSPERO(CRD42023427939) and performed according to PRISMA guidelines. From inception to November 15, 2023, a comprehensive search was conducted in PubMed, EMBASE, CINAHL, Web of Science, SCOPUS, PsycINFO, CNKI Database, Wanfang of Chinese Database, SinoMed Database and Cochrane Library on sexual functioning and childhood cancer survivors. Inclusion criteria were English or Chinese studies focusing on sexual functioning and related factors of cancer survivors, who diagnosed with cancer before 18 years old, and were adult and disease-free when participating in the study. Studies were excluded if the focus was on adult cancer patients or without age information. Findings: 395 records were retrieved, and 22 studies were finally included in this review. Results suggest that CCSs experience a substantial burden of sexual issues, including delayed psychosexual development, low satisfaction, and high prevalence of dysfunction. Underlying factors related to sexual functioning of CCSs were identified, including demographic, cancer treatment-related, psychological, and physiological factors. The historical change in research on sexual functioning was summarized. Interpretation: Research on sexual functioning among CCSs is limited. The extent to which cancer and related treatments affect sexual functioning remains largely unknown. The relationships between various factors and mechanisms underlying sexual functioning need to be confirmed by more rigorous studies to enable effective interventions to be developed. Funding: None.

Split ring hole metamaterial-enhanced pyroelectric detector for efficient multi-narrowband terahertz detection.

Derived from infrared pyroelectric detection, typical terahertz (THz) pyroelectric detectors have low sensitivity at low-frequency THz bands. Based on the high-efficiency absorption of the metamaterial perfect absorber (MPA), a novel split ring hole metamaterial-enhanced pyroelectric detector is proposed to achieve efficient multi-narrowband THz detection. Using high frequency simulation software (HFSS), the dimensional parameters including ring radius, ring width, connection beam width, array period, and thickness, are optimized to enhance efficient multi-narrowband absorption. The as-optimized metamaterial-enhanced detectors are fabricated via micro-nano manufacturing technology. The voltage responsiveness and noise equivalent power of the metamaterial-enhanced detector are tested by THz focused optical path and compared with those of the typical pyroelectric detector and the simulated MPA absorptivity. The results indicate that the metamaterial-enhanced detector has a multi-narrowband detection capability at 0.245 THz, 0.295 THz, and 0.38 THz, which is close to the simulated MPA absorptivity. Compared to the typical pyroelectric detector, the split ring hole metamaterial-enhanced detector can simultaneously achieve thermal absorption, thermal conduction, and pyroelectricity in the same MPA structure, providing faster response speed above 100 Hz chopper frequency and two times higher detection sensitivity at multi-narrowband THz frequencies. This research can be used for THz sensing, absorption filtering, biological macromolecule detection, and other applications.

Ebola virus-induced eye sequelae: a murine model for evaluating glycoprotein-targeting therapeutics.

BACKGROUND: Ebola virus disease (EVD) survivors experience ocular sequelae including retinal lesions, cataracts, and vision loss. While monoclonal antibodies targeting the Ebola virus glycoprotein (EBOV-GP) have shown promise in improving prognosis, their effectiveness in mitigating ocular sequelae remains uncertain. METHODS: We developed and characterized a BSL-2-compatible immunocompetent mouse model to evaluate therapeutics targeting EBOV-GP by inoculating neonatal mice with vesicular stomatitis virus expressing EBOV-GP (VSV-EBOV). To examine the impact of anti-EBOV-GP antibody treatment on acute retinitis and ocular sequelae, VSV-EBOV-infected mice were treated with polyclonal antibodies or monoclonal antibody preparations with antibody-dependent cellular cytotoxicity (ADCC-mAb) or neutralizing activity (NEUT-mAb). FINDINGS: Treatment with all anti-EBOV-GP antibodies tested dramatically reduced viremia and improved survival. Further, all treatments reduced the incidence of cataracts. However, NEUT-mAb alone or in combination with ADCC-mAb reduced viral load in the eyes, downregulated the ocular immune and inflammatory responses, and minimized retinal damage more effectively. INTERPRETATION: Anti-EBOV-GP antibodies can improve survival among EVD patients, but improved therapeutics are needed to reduce life altering sequelae. This animal model offers a new platform to examine the acute and long-term effect of the virus in the eye and the relative impact of therapeutic candidates targeting EBOV-GP. Results indicate that even antibodies that improve systemic viral clearance and survival can differ in their capacity to reduce acute ocular inflammation, and long-term retinal pathology and corneal degeneration. FUNDING: This study was partly supported by Postgraduate Research Fellowship Awards from ORISE through an interagency agreement between the US DOE and the US FDA.

MUC1-C regulates NEAT1 lncRNA expression and paraspeckle formation in cancer progression.

The MUC1 gene evolved in mammals for adaptation of barrier tissues in response to infections and damage. Paraspeckles are nuclear bodies formed on the NEAT1 lncRNA in response to loss of homeostasis. There is no known intersection of MUC1 with NEAT1 or paraspeckles. Here, we demonstrate that the MUC1-C subunit plays an essential role in regulating NEAT1 expression. MUC1-C activates the NEAT1 gene with induction of the NEAT1_1 and NEAT1_2 isoforms by NF-κB- and MYC-mediated mechanisms. MUC1-C/MYC signaling also induces expression of the SFPQ, NONO and FUS RNA binding proteins (RBPs) that associate with NEAT1_2 and are necessary for paraspeckle formation. MUC1-C integrates activation of NEAT1 and RBP-encoding genes by recruiting the PBAF chromatin remodeling complex and increasing chromatin accessibility of their respective regulatory regions. We further demonstrate that MUC1-C and NEAT1 form an auto-inductive pathway that drives common sets of genes conferring responses to inflammation and loss of homeostasis. Of functional significance, we find that the MUC1-C/NEAT1 pathway is of importance for the cancer stem cell (CSC) state and anti-cancer drug resistance. These findings identify a previously unrecognized role for MUC1-C in the regulation of NEAT1, RBPs, and paraspeckles that has been co-opted in promoting cancer progression.

Mitochondrial defects in sporadic inclusion body myositis-causes and consequences.

Sporadic inclusion body myositis (sIBM) is a distinct subcategory of Idiopathic Inflammatory Myopathies (IIM), characterized by unique pathological features such as muscle inflammation, rimmed vacuoles, and protein aggregation within the myofibers. Although hyperactivation of the immune system is widely believed as the primary cause of IIM, it is debated whether non-immune tissue dysfunction might contribute to the disease's onset as patients with sIBM are refractory to conventional immunosuppressant treatment. Moreover, the findings that mitochondrial dysfunction can elicit non-apoptotic programmed cell death and the subsequent immune response further support this hypothesis. Notably, abnormal mitochondrial structure and activities are more prominent in the muscle of sIBM than in other types of IIM, suggesting the presence of defective mitochondria might represent an overlooked contributor to the disease onset. The large-scale mitochondrial DNA deletion, aberrant protein aggregation, and slowed organelle turnover have provided mechanistic insights into the genesis of impaired mitochondria in sIBM. This article reviews the disease hallmarks of sIBM, the plausible contributors of mitochondrial damage in the sIBM muscle, and the immunological responses associated with mitochondrial perturbations. Additionally, the potential application of mitochondrial-targeted chemicals as a new treatment strategy to sIBM is explored and discussed.

Untargeted foodomics for authenticating the organic farming of water spinach (Ipomoea aquatica).

This study aimed to conduct a comprehensive analysis of the primary and secondary metabolites of water spinach (Ipomoea aquatica) using hydrophilic interaction liquid chromatography coupled with Orbitrap high-resolution mass spectrometry (HILIC-Orbitrap-HRMS). Certified samples from two cultivars, Green stem water spinach (G) and White stem water spinach (W) cultivated using organic and conventional farming methods, were collected from the Hong Kong market. Multivariate analysis was used to differentiate water spinach of different cultivars and farming methods. We identified 12 metabolites to distinguish between G and W, 26 metabolites to identify G from organic farming and 8 metabolites to identify W from organic farming. Then, two metabolites, isorhamnetin and jasmonic acid, have been proposed to serve as biomarkers for organic farming (in both G and W). Our foodomics findings provide useful tools for improving the crop performance of water spinach under abiotic/biotic stressesand authentication of organic produce.